This month Planet Earth reached a grim milestone - carbon dioxide emissions reached more than 400 parts per million average for a day, which is 50 ppm more than what scientists regard as the safe level for keeping the earth's temperature rise to 2 degrees Celsius above pre-industrial levels.

Now many scientists think we will have to fight hard to keep the temperature rise to less than 4 degrees, and are some are already warning of a horrendous 7-degree rise. Christine Lagarde, managing director of the IMF, warned that climate change is "the greatest economic challenge of the 21st century … Unless we take action on climate change, future generations will be roasted, toasted, fried and grilled."

Although Obama claims climate change is high on his agenda, he has been slow to do anything

Is this going to be yet another column of gloom and doom? I'm afraid there is little I can do in the face of large-scale carelessness, neglect and greed in the maintenance of our planet. But I hope that I may be able to add a shaft of sunlight to our plight.

The Council on Foreign Relations, the leading US think tank, last month issued a grim report card on climate change, giving the world a resounding "D", with the US earning a C-minus. The council assessed understanding of the threats of climate change as "good".

Performance is another matter: curbing emissions and promoting low-carbon development has been "poor", the council reported. Monitoring and enforcing emissions cuts is "average". Financing emissions cuts and adapting to climate change are both "poor"; and utilising carbon sinks is "incomplete".

All of the leading emitters apart from the Europeans are being irresponsible. Although the council claims understanding is "good", powerful voices in the US still can't see a problem.

This month, TheWall Street Journal published an editorial page article titled: "In defence of carbon dioxide: the demonised chemical compound is a boon to plant life and has little correlation with global temperature" - which is like saying that water is essential for life, so mass flooding is better.

Although US President Barack Obama claims climate change is high on his agenda, he has been slow to do anything. Fearing being stymied by Republicans in Congress, he is pushing the nebulous idea of "international peer pressure" to encourage nations to challenge each other to be greener.

This is unlikely to work. The BRICS collective (Brazil, Russia, India, China and South Africa) ganged up to prevent a climate deal. According to the 2012 Columbia and Yale University Environmental Performance Index, all BRICS except Brazil have been damaging their - and the earth's - ecology at the most rapid rate of any group of countries. China, South Africa and India have declining scores on greenhouse gas emissions.

China, which has taken over as the world's worst polluter, and India, demand that developed countries must first pay the price for their historic role in polluting the planet. As for Russia, the Council on Foreign Relations described it as "the class truant for its minimal engagement" in climate talks.

Nicholas Stern, the British economist and climate change expert, warned after the news that the 400 ppm level had been reached that it was likely to lead to a 5-degree rise in global temperatures, regular disruptions to global weather patterns and spreading deserts.

"Hundreds of millions of people will be forced to leave their homelands because their crops and animals will have died," warned Stern. "The trouble will come when they try to migrate into new lands, however. That will bring them into armed conflict with people already living there ... It could become a permanent feature of life on earth."

So where is the good news? Well, long-heralded renewable clean energy sources are finally arriving in economically efficient form. As The Economist noted, wind farms provide 2 per cent of the world's electricity and their contribution is doubling every three years, meaning that wind will overtake nuclear power in the next decade.

The greatest renewable hope is solar power, which today contributes less than 1 per cent to global electricity but is growing rapidly as the cost of solar panels drops sharply. Amory Lovins, chairman of the Rocky Mountain Institute, pointed out that new utility-scale solar power underbid efficient new gas-fired plants in California's 2011 spring auction. Early this year, Spain briefly achieved 61 per cent renewable power and Germany 70 per cent.

Wind and solar are on the way to becoming so cheap that Lovins says: "It doesn't matter if we never run out of oil: we won't want to burn it anymore."

It's a comforting thought, but renewable power still has to fight the battle against determined big oil paymasters of powerful politicians.

This week, the International Energy Agency heralded the prospect that massive American shale oil production would lead to the US becoming the world's biggest non-Opec producer. That's big bucks promoting carbon dioxide emissions.

Kevin Rafferty is a professor at the Institute for Academic Initiatives, Osaka University

This article appeared in the South China Morning Post print edition as Temperatures rise in fight to save planet, but solar power brings a ray of hope

If coal and oil remains to be the main source of energy supply for decades to come, the future of a livable environment is grim. Less grim therefore, the focus should be to improve the efficiency how coal and oil are being used to be the most advance. In fact it is to tackle air pollution at the source – mainly coal burning power generation electrical plants and oil burning vehicles, planes and ships. In Hong Kong, when talk about electrifying our transportation but without demanding improving coal burning as a source of electrical power it becomes a fool’s attempt to clean up our air and lessen its temperature rise. Relocating air pollution from roadside to smoke stakes only makes relief temporary until the location distinction becomes none. Hong Kong’s favorite podium design topping with residential towers, the fully built podiums contributes heat islands which have been found to raise the surroundings by as high as 5 degrees. No such design adoption should continue.